A team of art detectives is developing cutting-edge technology to try to solve
one of the Renaissance's most tantalising mysteries – the fate of a
long-lost Leonardo da Vinci masterpiece.

Prof Maurizio Seracini, who features in Dan Brown's The Da Vinci Code, plans to use 21st century technology to solve a 500-year-old puzzle.

He and his team are building two machines – a neutron beam scanner and a gamma-ray camera – which will be able to 'see' behind an existing Renaissance painting to determine whether it hides the earlier work by Leonardo, the Battle of Anghiari.

Prof Seracini believes that the battle tableau, started by Leonardo da Vinci around 1505, lies concealed behind the later work, which still decorates a great hall in Florence's medieval Palazzo Vecchio.

He has used thermal imaging to show that there is a narrow space in the wall behind the existing painting, The Battle of Marciano in the Chiana Valley, by Giorgio Vasari, another Renaissance master.

But only the gamma ray machine and neutron beam projector will be able to determine, once and for all, whether Leonardo's great work survived, protected over the centuries by the wall cavity, or whether it was destroyed and lost forever.

The team of scientific sleuths, based at the University of California, San Diego, say the two devices will be able to detect the organic matter in oil paints and natural pigments. But they need $2.5 million to finish the project.

"This sort of technology has never been applied to art or architecture," Prof Seracini told The Daily Telegraph on Wednesday as he stood beneath the immense Battle of Marciano painting in the palazzo's Hall of the Five Hundred.

"We have the technology to give final proof that the Battle of Anghiari is still there. It is now simply a matter of money. It would probably be in good shape, because it has been sealed away all this time."

Prof Seracini, an engineer by training, believes a cryptic clue in Vasari's art work suggests that he preserved Leonardo's masterpiece by building the false wall.

A small green banner held by soldiers at the top of the painting bears the words "Cerca, trova" – "Search, and you will find." "There are six paintings decorating the walls of the hall and these are the only words to appear anywhere," he said. "Why would you bother painting them, all the way up there where they are difficult to see, if they didn't mean something?"